1. Field of the Invention
The invention relates to a self-propelled road milling machine which comprises a machine frame which is supported by a chassis and a working device having a work roller which comprises work tools, wherein the chassis of the road milling machine comprises two rear wheels or running gears and at least one front wheel or running gear.
2. Description of the Prior Art
A road milling machine having a milling roller arranged at the rear of the machine and a chassis which comprises two rear wheels and two front wheels is known from DE 196 31 042 A1 (U.S. Pat. No. 6,106,073A). The milling roller is arranged between the rear wheels. In the known road milling machine, one of the two rear wheels can be pivoted out of an outer position in relation to a longitudinal side of the machine frame, which position corresponds to the normal position, and into an inner position in relation to the longitudinal side of the machine frame. When the rear wheel is in the inner position, the milling roller of the milling machine can move closely past an obstacle since the rear wheel does not laterally protrude beyond the milling roller in this position.
The material removed by the milling tools of the milling roller as the road milling machine advances is picked up by a transport device so that the material can be loaded onto a lorry. However, the transport device cannot pick up all of the material removed, and therefore material is left lying on the terrain.
The milled material left lying on the terrain could subsequently be removed by means of a sweeping machine. Attempts have also been made to pick up the material using a sweeping device which is fixed to the milling machine and has a rotating roller brush arranged behind the milling roller in the working direction. However, until now equipping milling machines with a sweeping device has been disregarded since it is more cost-effective to use a separate sweeping machine. Until now, experts have seen no reason to clean the surface of the terrain in front of a road milling machine and over which the road milling machine travels. Thus milling machines having a sweeping device have not gained currency either.
The problem when using the known road milling machines is that, in particular in small millers due to the small milling width, the road surface has to be milled off in a plurality of closely adjacent milling steps. When the road surface is milled off by the road milling machines, in particular small millers, in a plurality of milling sections, in certain cases an optimum milling result is not achieved.